The present invention relates to an adsorptional heat pump, and more particularly to an adsorptional heat pump including a plurality of sector modules of which each module is connected to an opposite module by a thermosyphon in order to exchange heat therebetween.
Generally, conventional heat pumps are classified as one of two types, that is, an absorptional heat pump and an adsorptional heat pump. Of the two types, the adsorptional heat pump is more advantageous than the absorptional heat pump in performance thereof, such as starting performance and leakage prevention, etc.
The adsorptional heat pumps generally comprise a container containing a condenser and an evaporator, an adsorber or a generator which alternatively and repeatedly carries out an adsorption or generation of refrigerants wherein solid zeolites are used as adsorbents.
The driving principles of the adsorptional heat pumps are now described with reference to FIGS. 1A-1C.
FIG. 1A describes a generating/condensing process, and then, FIG. 1B describes an adsorbing/evaporating process. FIG. 1C is a T-P diagram showing relations between temperature and pressure of each step. As shown in FIGS. 1A and 1B, the adsorptional heat pumps comprise a generator/adsorber 2 which contains solid zeolites 1 as an adsorbent therein, and alternatively and repeatedly generates and adsorbs refrigerants by using heat from an outside heat source, a condenser 3, an accumulator 4 for containing condensed refrigerants and an evaporator 5 which are connected to the generator/adsorber 2.
In the generating/condensing process (FIG. 1A), the pressure in the generator/adsorber 2 rises by a heat of generation QH, so that the refrigerants are generated. Thereafter, the generated refrigerants (vapors) are fed to the condenser 3 in which a condensation of the generated refrigerants is simultaneous with an emission of a heat of condensation Q.sub.K. The heat of condensation Q.sub.K being obtained from the condenser 3 is used for heating the interior of a room in heating operation or emitted into the atmosphere in cooling operation.
Also, as shown in FIG. 13, in the adsorbing/evaporating process, the refrigerants in the evaporator 5 are evaporated by receiving a heat of evaporation Q.sub.O from the outside, and then, the evaporated refrigerants are fed to the generator/adsorber 2 in which an adsorption of the evaporated refrigerants with the zeolites 1 is simultaneous with an emission of a heat of adsorption Q.sub.A. In heating operation, the emitted heat of adsorption Q.sub.A is used for heating the interior of the room, the cooling of the interior is carried out by the evaporating process wherein the heat of evaporation Q.sub.O s received from the interior into the heat pump. Accordingly, the adsorptional heat pump alternatively and repeatedly carries out the generating/condensing process or the adsorbing/evaporating process, so that the adsorptional heat pump heats or cools the interior of the room.
However, because it is necessary for the adsorptional heat pump to repeatedly and periodically be heated or emit the heat in periodical and repeated generating/condensing process or adsorbing/evaporating process thereof, the adsorptional heat pump has a fault that the supplying or the withdrawal of the heat happens intermittently. Therefore, the adsorptional heat pumps are not appropriate for a general cooling/heating apparatus which needs a continuous supply of the heat.
Also, in attempts to solve the above-mentioned fault, there is a conventional adsorptional heat pump in which heated heat mediums are alternatively supplied by a valve to a pair of generators/adsorbers in order to alternatively generate or adsorb the refrigerants in the generators/adsorbers. But, the heat pumps also have the problems that the control of the pumps is difficult and the supply of the heat from the pumps is intermittent because the supplying direction of the heated heat mediums must be repeatedly changed by an actuation of the valve.
In order to solve the intermittent supply of the heat from the pump and the complexity of the valve control, adsorptional heat pumps with a pair of rotary module discs are proposed as described in German Patent No. 3,342,985Al.
As described in FIGS. 2A and 2B, the above-mentioned heat pump includes upper and lower rotary module discs which rotate in opposite directions and comprise plurality of modules which are connected with each other via an internal heat exchanging means containing a heat medium such as an oil for internal heat exchange between the two opposite modules.
FIG. 2A is a front view of the rotary module discs of the adsorptional heat pump, and FIG. 2B is a cross-sectional view taken along the line A--A of FIG. 2A. As shown in FIGS. 2A and 2B each one of the rotary module discs 6,7 comprises plurality of sector modules, and contains zeolites 8 in a peripheral container thereof. Also, between the upper and lower module discs 6,7, there is an internal heat exchanging means 10 of pipe style which contains heat mediums 9 and connects each module to an opposite module.
In the adsorptional heat pumps with rotary module discs, an outside portion of each sector module functions as a generator/adsorber 11, and then, an inside portion of the sector module functions as a condenser/evaporator 12. Therefore, according to a rotation of the rotary module discs, each sector module repeatedly acts a cyclic process comprising generation.fwdarw.heat exchange.fwdarw.adsorption.fwdarw.heat exchange.fwdarw.generation.
In FIGS. 2, numerals 13 and 14 describe a cooling fan and a blower respectively.
As described in FIG. 2B, the refrigerant in adsorption with the zeolites 8 is generated by a burnt gas (g) passing from the lower of the adsorber 11. Also, the generated refrigerants are fed to the condenser 12 in which the refrigerants are cooled and condensed by the cooling fan 13 maintaining a fixed position in spite of the rotation of the module disc.
Thereafter, a module accomplishing the generating process transfers heat to an opposite module in order to cool the interior thereof. Also, a module accomplishing the adsorbing process obtains heat, therefore, the module can reduce a quantity of the heat of generation Q.sub.H necessary in generation of the refrigerant in the consequent processes.
As above described, in the adsorptional heat pump with rotary module discs, the upper and lower discs rotate in the opposite directions and the opposite modules exchange heat with each other through the heat mediums in the heat exchanging means positioned between the two rotary module discs. Accordingly, there is an advantage of promoting COP of the heat pump because an efficiency being similar to that of heat exchange using a counter flow heat exchanger can be provided in the heat exchanging means of the heat pump.
However, there are some problems in that the use of a heat transferring feature of the heat mediums such as an oil limits heat exchanging performance, that it is difficult to seal the heat exchanging means and that the complex construction of the heat exchanging means enlarges the size of the heat pump.